There are a number of exercise devices that operate to allow a user to implement a foot action following a generally closed, curved path of travel, simulating running and/or walking. These devices are generally referred to as “elliptical” exercise devices. Many such elliptical exercise devices are large, complicated, costly, and/or have undesirable characteristics related to the motion of the user's feet.
U.S. Pat. No. 5,518,473 to Miller shows an early design for an elliptical exercise device. The device provides a path of travel that simulates running and/or walking but is quite large and does not provide for arm exercise.
U.S. Pat. No. 5,611,756 to Miller discloses an elliptical exercise device with arm and leg movement. A pair of guide links is pivotally supported on a frame and a foot engaging link is supported at the lower end of each guide link. An intermediate link connects each guide link to A crank. A control link joins each foot link to the corresponding intermediate link to vary the angle of the foot link relative to the guide link.
U.S. Pat. No. 6,045,487 to Miller discloses an elliptical exercise device having a pair of guide links pivotally supported on a frame and a foot link supported at the lower end of each guide link. An intermediate link connects each guide link to a crank of a crank system. A flexible control member engages each foot link and extends up and over a pulley located at the guide link pivot axis. The control members connect to a reciprocating assembly for moving the foot links up and down as the guide links pivot back and forth.
U.S. Pat. No. 7,708,668 to Rodgers. Jr. shows several embodiments of an exercise device having flexible elements coupling left and right foot support members to a crank system. The exercise device allows for a variable stride length and decouples the vertical and horizontal components of foot travel.
U.S. Pat. No. 7,556,591 to Chuang et al. discloses an exercise device with cranks mounted to an upper portion of a frame. Two handles are pivoted to the frame forward of the cranks. Foot supports are pivotally coupled to the lower ends of the handles. Pivot rods extend between each foot support and one of the cranks. Additional links connect each handle with the same cranks as the respective pivot rod.
U.S. Pat. No. 8,979,714 to Miller discloses an elliptical exercise device having a frame supporting guide links which provide for horizontal motion of associated foot support links. A mechanical coupling couples the foot support links to the crank system and intermediate links connect the crank system to the guide links such that a foot receiving area of each foot support link moves in an elliptical path when the crank system rotates.
U.S. Pat. No. 9,192,809 to Miller et al. discloses an elliptical exercise device with a frame supporting guide links and foot support links. Upper pulleys are pivotally connected to the frame or guide links, front lower pulleys are connected to the guide links or foot support links and rear lower pulleys are connected to the foot support links. A flexible element extends from a vertical drive assembly to the upper pulley, front lower pulley, rear lower pulley and then to the frame rearward of the guide link pivot.
Additional exercise devices will be known to those of skill in the art.